Pier door



May 8, 1923. I 1,454.125

j L. MCHARG PIER DOOR.

Filed Aug. 30 1921 2 Sheets Sheet 2 Patented May 8, 1923.

LESLIE MOHARG, OF FREEPOR'I', NEW YORK.

PIER DOOR.

Application filed August 30, 1921. Serial No. 496,800.

T all whom it may concern:

Be it known that I, LESLIE McHARo, a citizen of the United States ofAmerica, residing at F reeport, in the county of Nassau and State of NewYork, have invented certain new and useful Improvements in Pier Doors,of which the following is a full, clear, and exact description.

In a patent granted to me on February 22, 1921, No. 1,369,425, I haveshown and described a pier shed door in which the door is composed oftwo sections the lower section of which, by suitable means, israiseduntil it fully overlaps the upper section, whereupon both overlappingsections are simultaneously caused to travel upwardly and outwardly bygrooved guides with which they engage into a substantially horizontalposition. Y

In the mechanism shown in the patent for accomplishing this result acounterbalancing weight is used on each side of the door, and twopulleys are employed at opposite ends of a rotary shaft over whichchains carrying the weights run, one end of each chain being connectedto the bottom of the edge of the lower section and the other to anintermediate part of the edge of the upper section,

It resulted from this arrangement that more space was necessary for thedoor and its counterbalancing weights than was de sirable, and that whenthe doorwasfully opened the angle of the chains connected with themiddle of the upper sect-ion to the normal plane of the pulleys to whichsaid chains led was such that the chain was liable to run out of thepulley groove, or caused undue friction and wear on the pulley.

These defects it was my object to avoid in devising and constructing theform of li-fting mechanism upon which is based my pres ent applicationfor Letters Patent.

My improvements, in general terms, con

sist in dispensing with the overhead rotary shaft in the use of a singleweight connected to lifting chains running over a special arrangement ofpulleys, and in swivelling that pulley at each side of the door overwhich runs the chain connected wi h the middle of the upper section ofthe door. so'that when the door is fully opened or substantially so,

' the pulley will assume an angle to the vertical which 1 for the angleof the chain.

These improvements are illustrated in the accompanying drawings, inwhich:

igure '1 is an edge View in elevationof the improved door.

corresponds to and compensates Fig. 2 is a sectional view of one side ofthe door on the line 2-2 of Fig. 1. Fig. 3 is a front elevation of thedoor. F 1g. 4 is a top plan view of the same. Fig. 5 is a detailed viewof one form. of

a part of the lifting mechanism; and,

Fig. 6 is an illustrative diagram to illustrate the operation of thedoor. r i

-The door proper may be composed either of two sections adapted tooverlap, or of .a single section,

projections 3 which in practice should be rollers to avoid friction, butwhen raised, is

since the character'of "the device as a whole-requires butlittl'eiheadother proper guide 1'is caused to assume a nearly horizontalposition, as shown in dotted lines in Fig. 1. The theory of theconstruction and-operation of the in Figs. 4 and 6, to which referencefor the moment is made. At each side of the door 2 and above it, twoloose pulleys .4, 5, 6, T are supported by suitable brackets 8 and onone side of the door a shaft at ri ht angles to the plane of the door ismounted on which are four pulleys 9, 10,11, 12 as nearly as practicable,in the plane of the others, and a winding pulley or'sprocket pulleys 9and 10 are fixed to the shaft and 11 and 12 are loose. 1 Over pulley 13pames a hand chain 14. shown in Fig. 3, by means of. which the pulleys 9and 10 are rotated.

Chains or preferably wire ropes 15, 16 and which I shall hereinafterrefer to as cords, run over the pulleys in the following manner, thepulleys being shown in the diagram Fig. 6, as of different diameters forsake of illustration. One end of cord 15 is connected to the bottom ofthe edge of the door and runs up over the pulley 4,

13. Of these thence over fixed pulley 10, thence over one of two idlers17 in a bracket from which the weight 18 is suspended, thence over theloose pulley 12, thence over pulley 5, and down to the middle orapproximately such point on the same edge of the door.

In like manner the cord 16 passes over pulleys 6, 7, 9, 11 andthe otheridler 17, so that when the pulleys 9 and 10 are rotated by the handchain 14, the door is' drawn up by the 7 weight 18 and the force appliedto the fixed pulleys.' v As the door rises its upper edge follows theguides'land the door ultimately lies out in the substantially horizontalposition shown in Fig. 1, but in this positionit will be seen that theportions of the suspending cordsconnected withthe middle oftheidoor lieat an angle to the normal plane of the pulleys over which they run.shown clearly in Fig. 1.

from the grooved pulleys, to prevent which the two pulleys 5 and 7 areswivellcd,as

indicated, so that in swinging they follow the angle of the cords asindicated in dotted indicated in Flg. 6, or the cords must passsubstantially through the centers around which the swivelled pulleysturn, as indicatedin detail in Fig. 5, where the cord is shown aspassing through an "opening 19.

This pier door is an improvement on those now in general use in that-iteconomizes space and parts. The power required to open and close thedoor is uniform in all positions of the door, and the effects offriction are greatly reduced. The means combined action of the.

This is- Under such cir-' cumstances the'cords are liable to pull offfor controlling the door are very simple and not liable to wear orderangement.

What I claim is 1. The combination with a pier shed door of a drivingshaft for controlling the same supported at one side of the door, fourpulleys on said shaft, two fixed and two loose,

which in opening assumes a horizontal position, of two loose pulleys,over each upper corner of the door, weighted cords running over suchpulleys and means for-operating the same for opening or closing thedoor, one end ofeach cord being connected to the bottom and the otherendto the middle portion of-the edge of the door, and that loose pulley ofeach pair over which the cord connectedto the middle of the door 7 runsbeing swivelled so as to follow the angle of such cord" when "the dooris brought to'a horizontal position. I 3 The combination with a piershed door which in opening shifts from a vertical'to a horizontalposition, of a pair of loose pulleysove'r each upper corner of the same,one

of eachpair being swivlled, two driving and two loose pulleys at oneside of the door andweighted cords passing over all of said pulleys andhaving their ends connected respectively with the bottom and middlepoints of the edges of the door, the end of the cords connected with themiddle running over the swiveled pulleys, for the purpose set forth.

In testimony whereof I hereto afiix my signature.

LESLIE MoHARG.

